Drawing Polyethylene (PE) fiber (a process where a thermoplastic yarn is heated and elongated to result in a stronger but thinner yarn) is a well-known process, and has been used to increase strength of fibrous materials. Drawing PE fiber allows tremendous flexibility in final product sizing, oftentimes producing different products from the same feeder stock.
By changing the draw ratio during a production run, it is possible to create a tapered line that has a thick section (lower draw ratio, e.g. 1.1×) and a thinner section (higher draw ratio, e.g. 2.0×). In one example, the thick portion of the taper is 50% stronger than the thin portion.
The purpose of the thicker, stronger section is to have enough strength to offset the reduction due to making a knot. A good knot in 80 lb line breaks around 50 lbs. By creating a line with 80 lbs in a thicker section (designated for knot tying), and then tapering down to 50 lbs in the thinner section, one creates a line that has the same load carrying performance as an all 80 lb line, yet with increased capacity on the reel (and reduced drag in the water) because the line is not all at the thicker diameter. The thick/thin section may repeat, for example, every 25 feet to allow anglers to cut off only 25 feet each time they exhaust the thicker knot section of the line.
Production rates are affected by dwell time in heat transfer media. For example, if it takes 20 seconds to heat and draw braid to a desired ratio, the longer the “oven” (or heat transfer device) the faster the output. Here, the word “oven” indicates an intuitive concept of any heat transfer media. A double length of oven will allow double output speed at a given temperature. However, the draw happens throughout the length of the oven, so as long as one is making a constant diameter product there is no production penalty.
In the specific case of a tapered line of the invention, it is desired to taper from the thin portion to the thicker portion of the line within a short period or length. This requires a short oven to localize the taper. However, the throughput cost of such a short oven may be 10× slower than the regular process due to long dwell time, thus resulting in a cost-prohibitive process. With the invention herein disclosed, a reduced processing time to between 2× to 3× is achieved.
Therefore, there is a long-felt need for a production device and method that can efficiently and effectively yield a tapered line of varying thickness. The present device and method of operation addresses and solves these needs. The present invention relates to a device and method for efficient production of tapered fishing line through the use of heat transfer media. The device and method allow, among other things, a means to create tapered fishing line with minimal transitional distances between tapered sections and may operate at higher rates of production than conventionally provided.
By way of providing additional background and context, the following reference is incorporated by reference in its entirety for the purpose of explaining various methods of tapering fishing lines: U.S. Pat. No. 7,081,298 to Nakanishi.